Field of the Invention
The present invention relates to a light module for a vehicle, which achieves improved luminance efficiency of beam scanning.
Description of Related Art
Generally, a vehicle is provided with a lighting apparatus, which serves to assist a driver in clearly viewing objects in a driving direction at night, and to notify other vehicles or persons on the road of the state of driving of the owner's vehicle.
In addition to simply emitting light, in recent years, a technology of projecting a specific image to increase the driver's convenience and various other functions have been added to the lighting apparatus.
In order to realize beam scanning of the lighting apparatus, laser scanning devices using a polygon mirror and a galvanometer mirror have been applied. However, the polygon mirror and the galvanometer mirror are plagued with problems related to size reduction and high prices.
Therefore, a beam scanning device using a Micro Electro Mechanical System (MEMS) mirror is used. The beam scanning device using the MEMS mirror advantageously exhibits low power consumption and may be reduced in size.
However, the MEMS mirror vibrates in the left-and-right direction during laser beam scanning using the MEMS mirror, causing deterioration in the brightness of the central portion compared to the edge portion. That is, because the light reflected by the MEMS mirror shows a pattern of motion from the upper side to the lower side in the left-and-right direction, laser beams overlap each other in the edge portion in the left-and-right direction, which causes deterioration in the brightness of the central portion compared to the edge portion.
Because a headlamp requires the highest brightness in the central portion, this deterioration in the brightness of the central portion results in deterioration in the luminance efficiency of the headlamp.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.